Data transmission management in Radio Resource Control (RRC) inactive state

The present application is a National Stage application, filed under 35 U.S.C. § 371, of International Patent Application Serial No. PCT/CN2021/093616, filed on May 13, 2021, which claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 63/024,409, filed on May 13, 2020. The contents of each of the above-referenced applications are hereby incorporated fully by reference into the present application.

The present disclosure generally relates to wireless communications and, more particularly, to management of data transmission by a user equipment (UE) while the UE is in an RRC_INACTIVE state in next-generation wireless networks.

With the tremendous growth in the number of connected devices and the rapid increase in user/network traffic volume, various efforts have been made to improve different aspects of wireless communication for the next-generation wireless communication system, such as the fifth-generation (5G) New Radio (NR) system, by improving data rate, latency, reliability, and mobility. The 5G NR system is designed to provide flexibility and configurability to optimize the network services and types, accommodating various use cases, such as enhanced Mobile Broadband (eMBB), massive Machine-Type Communication (mMTC), and Ultra-Reliable and Low-Latency Communication (URLLC).

In NR, a User Equipment (UE) may operate in, and transition between, various Radio Resource Control (RRC) states within a next generation radio access network (RAN). These different states include an RRC Connected state, an RRC Idle state, and a newly added state which is known as an RRC_INACTIVE state. UEs with infrequent (e.g., periodic and/or non-periodic) data transmissions are generally maintained by the network in the RRC_INACTIVE state. A UE in the RRC_INACTIVE state originally was not able to transmit data and had to resume the connection (e.g., move/transition to an RRC_CONNECTED state) for any downlink (DL) data reception and/or uplink (UL) data transmission. Scheduling of resources (and subsequent release of the resources), therefore, had to occur for each data transmission, regardless of how small and infrequent the data packets of each transmission were. This resulted in unnecessary power consumption and signaling overhead.

Signaling overhead due to transmission of small data packets in the UEs that are in an Inactive state can be a general problem that may become a critical issue as the number of UEs increases, not only for the network performance and efficiency, but also for the UE's battery performance. In general, any device that has to transmit intermittent small data packets may benefit from enabling small data transmission in the Inactive state. To enable small data transmission in the Inactive state, the 3rd Generation Partnership Project (3GPP) has recently introduced some mechanisms that utilize, for example, 2-step and/or 4-step random access channel (RACH) procedures and/or configured grant (e.g., Type 1 CG) in the Inactive state. However, further improvements are needed in a small data transmission mechanism while a UE is in an RRC_INACTIVE state.

The present disclosure is directed to management of data transmission by a user equipment (UE) while the UE is in an RRC_INACTIVE state.

In a first aspect of the present application, a method performed by a user equipment (UE) for transmitting uplink (UL) data in a radio resource control (RRC)_INACTIVE state is provided. The method includes receiving, from a serving cell, a configuration of at least one UL resource associated with a normal UL (NUL) frequency carrier and a supplementary UL (SUL) frequency carrier of a plurality of UL frequency carriers; selecting one of the NUL frequency carrier or the SUL frequency carrier; initiating a small data transmission (SDT) procedure in the RRC_INACTIVE state to transmit, to the serving cell, at least one UL packet on the selected one of the NUL frequency carrier or the SUL frequency carrier via the at least one UL resource; and stopping the SDT procedure in a case that at least one predefined condition is fulfilled.

In an implementation of the first aspect, the at least one predefined condition includes at least one of the following: a cell reselection has occurred; an access stratum (AS) security error has occurred; an indication that a maximum number of retransmissions in a radio link control (RLC) layer has been reached; a random access problem has occurred; or a timing advanced (TA) timer associated with a UL configured grant (CG) for the SDT procedure has expired.

In another implementation of the first aspect, the at least one UL resource includes a CG resource and a random access (RA) resource, and one of the CG resource or the RA resource is associated with the NUL frequency carrier and the other one of the CG resource or the RA resource is associated with the SUL frequency carrier for the UE to transmit the at least one UL packet to the serving cell in the RRC_INACTIVE state.

In another implementation of the first aspect, selecting the one of the NUL frequency carrier or the SUL frequency carrier includes selecting any of the NUL frequency carrier or the SUL frequency carrier with which the CG resource is associated based on the CG resource having a higher priority than the RA resource.

In another implementation of the first aspect, selecting the one of the NUL frequency carrier or the SUL frequency carrier includes selecting any of the NUL frequency carrier or the SUL frequency carrier with which the RA resource is associated in a case that: the CG resource is not available, or the UE receives an indication from the serving cell that indicates to the UE to fallback from the CG resource to the RA resource for UL packet transmission.

In another implementation of the first aspect, the RA resource includes one of a 2-step RA resource and a 4-step RA resource, and the UE selects one of the 2-step RA resource or the 4-step RA resource for UL packet transmission based on a downlink (DL)-reference signal received power (RSRP) threshold associated with a type of the RA resource.

In another implementation of the first aspect, a first DL-RSRP threshold is configured by the serving cell to be associated with the NUL frequency carrier, a second DL-RSRP threshold is configured by the serving cell to be associated with the SUL frequency carrier, and the DL-RSRP threshold associated with the type of the RA resource is further associated with the selected one of the NUL frequency carrier or the SUL frequency carrier based on the first DL-RSRP threshold or the second DL-RSRP threshold.

In another implementation of the first aspect, the at least one UL resource includes a first UL resource and a second UL resource, wherein selecting the one of the NUL frequency carrier or the SUL frequency carrier includes receiving, from the serving cell, through dedicated control signaling, a downlink (DL)-reference signal received power (RSRP) threshold; selecting the one of the NUL frequency carrier or the SUL frequency carrier based on the DL-RSRP threshold; and after selecting the one of the NUL frequency carrier or the SUL frequency carrier, selecting one of the first UL resource or the second UL resource assigned to the selected one of the NUL frequency carrier or the SUL frequency carrier for transmitting the at least one UL packet to the serving cell.

In another implementation of the first aspect, the method further includes, after the at least one UL packet is transmitted to the serving cell using the NUL frequency carrier, determining that the at least one UL packet is to be retransmitted to the serving cell; and retransmitting the at least one UL packet using the NUL frequency carrier without using any other one of the plurality of UL frequency carriers, wherein retransmitting the at least one UL packet includes one of a Hybrid Automatic Repeat Request (HARQ) retransmission or an Automatic Repeat Request (ARQ) retransmission.

In another implementation of the first aspect, the at least one UL packet includes a first packet and a second packet, wherein transmitting the at least one UL packet includes transmitting, to the serving cell, the first UL packet and the second UL packet on the selected one of the NUL frequency carrier or the SUL frequency carrier without using any other one of the plurality of UL frequency carriers for transmitting the second UL packet.

In a second aspect, a UE including at least one processor and one or more non-transitory computer-readable media coupled to the at least one processor and configured to store computer-executable instructions is provided. When executed by the at least one processor, the computer-executable instructions cause the UE to receive, from a serving cell, a configuration of at least one UL resource associated with an NUL frequency carrier and an SUL frequency carrier of a plurality of UL frequency carriers; select one of the NUL frequency carrier or the SUL frequency carrier; initiate an SDT procedure in the RRC_INACTIVE state to transmit, to the serving cell, at least one UL packet on the selected one of the NUL frequency carrier or the SUL frequency carrier via the at least one UL resource; and stop the SDT procedure in a case that at least one predefined condition is fulfilled.

The acronyms in the present application are defined as follows and unless otherwise specified, the acronyms have the following meanings:

The following description contains specific information pertaining to example implementations in the present disclosure. The drawings in the present disclosure and their accompanying detailed description are directed to merely example implementations. However, the present disclosure is not limited to merely these example implementations. Other variations and implementations of the present disclosure will occur to those skilled in the art. Unless noted otherwise, like or corresponding elements among the figures may be indicated by like or corresponding reference numerals. Moreover, the drawings and illustrations in the present disclosure are generally not to scale and are not intended to correspond to actual relative dimensions.

For the purposes of consistency and ease of understanding, like features may be identified (although, in some examples, not shown) by the same numerals in the example figures. However, the features in different implementations may be differed in other respects, and thus shall not be narrowly confined to what is shown in the figures.

The description uses the phrases “in one implementation,” or “in some implementations,” which may each refer to one or more of the same or different implementations. The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series, and the equivalent. The expression “at least one of A, B and C” or “at least one of the following: A, B and C” means “only A, or only B, or only C, or any combination of A, B and C.”

Additionally, for the purposes of explanation and non-limitation, specific details, such as functional entities, techniques, protocols, standard, and the like are set forth for providing an understanding of the described technology. In other examples, detailed description of well-known methods, technologies, systems, architectures, and the like are omitted so as not to obscure the description with unnecessary details.

Persons skilled in the art will immediately recognize that any network function(s) or algorithm(s) described in the present disclosure may be implemented by hardware, software, or a combination of software and hardware. Described functions may correspond to modules which may be software, hardware, firmware, or any combination thereof. The software implementation may comprise computer-executable instructions stored on computer-readable medium, such as memory or other type of storage devices. For example, one or more microprocessors or general-purpose computers with communication processing capability may be programmed with corresponding executable instructions and carry out the described network function(s) or algorithm(s). The microprocessors or general-purpose computers may be formed of Application-Specific Integrated Circuits (ASICs), programmable logic arrays, and/or one or more Digital Signal Processor (DSPs). Although some of the example implementations described in this specification are oriented to software installed and executing on computer hardware, nevertheless, alternative example implementations implemented as firmware, as hardware, or as a combination of hardware and software are well within the scope of the present disclosure.

The computer-readable medium includes but is not limited to Random Access Memory (RAM), Read Only Memory (ROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), flash memory, Compact Disc Read-Only Memory (CD-ROM), magnetic cassettes, magnetic tape, magnetic disk storage, or any other equivalent medium capable of storing computer-readable instructions.

A radio communication network architecture (e.g., a Long-Term Evolution (LTE) system, an LTE-Advanced (LTE-A) system, an LTE-Advanced Pro system, or a 5G NR Radio Access Network (RAN)) typically includes at least one base station, at least one UE, and one or more optional network elements that provide connection towards a network. The UE communicates with the network (e.g., a Core Network (CN), an Evolved Packet Core (EPC) network, an Evolved Universal Terrestrial Radio Access network (E-UTRAN), a 5G Core (5GC), or an internet), through a RAN established by one or more base stations.

It should be noted that, in the present application, a UE may include, but is not limited to, a mobile station, a mobile terminal or device, a user communication radio terminal. For example, a UE may be a portable radio equipment, which includes, but is not limited to, a mobile phone, a tablet, a wearable device, a sensor, a vehicle, or a Personal Digital Assistant (PDA) with wireless communication capability. The UE is configured to receive and transmit signals over an air interface to one or more cells in a radio access network.

A base station may be configured to provide communication services according to at least one of the following Radio Access Technologies (RATs): Worldwide Interoperability for Microwave Access (WiMAX), Global System for Mobile communications (GSM, often referred to as 2G), GSM Enhanced Data rates for GSM Evolution (EDGE) Radio Access Network (GERAN), General Packet Radio Service (GPRS), Universal Mobile Telecommunication System (UMTS, often referred to as 3G) based on basic wideband-code division multiple access (W-CDMA), high-speed packet access (HSPA), LTE, LTE-A, eLTE (evolved LTE, e.g., LTE connected to 5GC), NR (often referred to as 5G), and/or LTE-A Pro. However, the scope of the present application should not be limited to the above-mentioned protocols.

A base station may include, but is not limited to, a node B (NB) as in the UNITS, an evolved node B (eNB) as in the LTE or LTE-A, a radio network controller (RNC) as in the UNITS, a base station controller (BSC) as in the GSM/GSM Enhanced Data rates for GSM Evolution (EDGE) Radio Access Network (GERAN), a next-generation eNB (ng-eNB) as in an Evolved Universal Terrestrial Radio Access (E-UTRA) BS in connection with the 5GC, a next-generation Node B (gNB) as in the 5G Access Network (5G-AN), and any other apparatus capable of controlling radio communication and managing radio resources within a cell. The BS may connect to serve the one or more UEs through a radio interface to the network.

The base station may be operable to provide radio coverage to a specific geographical area using a plurality of cells included in the RAN. The BS may support the operations of the cells. Each cell may be operable to provide services to at least one UE within its radio coverage. Specifically, each cell (often referred to as a serving cell) may provide services to serve one or more UEs within its radio coverage (e.g., each cell schedules the Downlink (DL) and optionally Uplink (UL) resources to at least one UE within its radio coverage for DL and optionally UL packet transmission). The BS may communicate with one or more UEs in the radio communication system through the plurality of cells.

A cell may allocate sidelink (SL) resources for supporting Proximity Service (ProSe) or Vehicle to Everything (V2X) services. Each cell may have overlapped coverage areas with other cells. In Multi-RAT Dual Connectivity (MR-DC) cases, the primary cell of a Master Cell Group (MCG) or a Secondary Cell Group (SCG) may be referred to as a Special Cell (SpCell). A Primary Cell (PCell) may refer to the SpCell of an MCG. A Primary SCG Cell (PSCell) may refer to the SpCell of an SCG. MCG may refer to a group of serving cells associated with the Master Node (MN), including the SpCell and optionally one or more Secondary Cells (SCells). An SCG may refer to a group of serving cells associated with the Secondary Node (SN), including the SpCell and optionally one or more SCells.

As discussed above, the frame structure for NR is to support flexible configurations for accommodating various next generation (e.g., 5G) communication requirements, such as Enhanced Mobile Broadband (eMBB), Massive Machine Type Communication (mMTC), Ultra-Reliable and Low-Latency Communication (URLLC), while fulfilling high reliability, high data rate, and low latency requirements. The Orthogonal Frequency-Division Multiplexing (OFDM) technology as agreed in 3GPP may serve as a baseline for NR waveform. The scalable OFDM numerology, such as the adaptive sub-carrier spacing, the channel bandwidth, and the Cyclic Prefix (CP), may also be used. Additionally, two coding schemes are considered for NR: (1) Low-Density Parity-Check (LDPC) code and (2) Polar Code. The coding scheme adaption may be configured based on the channel conditions and/or the service applications.

Moreover, it is also considered that in a transmission time interval TX of a single NR frame, a downlink (DL) transmission data, a guard period, and an uplink (UL) transmission data should at least be included, where the respective portions of the DL transmission data, the guard period, and the UL transmission data should also be configurable, for example, based on the network dynamics of NR. In addition, sidelink resources may also be provided in an NR frame to support ProSe services or V2X services.

In addition, the terms “system” and “network” herein may be used interchangeably. The term “and/or” herein is only an association relationship for describing associated objects, and represents that three relationships may exist. For example, A and/or B may indicate that: A exists alone, A and B exist at the same time, or B exists alone. In addition, the character “/” herein generally represents that the former and latter associated objects are in an “or” relationship.

As discussed above, the next-generation (e.g., 5G NR) wireless network is envisioned to support more capacity, data, and services. A UE configured with multi-connectivity may connect to a Master Node (MN) as an anchor and one or more Secondary Nodes (SNs) for data delivery. Each one of these nodes may be formed by a cell group that includes one or more cells. For example, an MN may be formed by a Master Cell Group (MCG), and an SN may be formed by a Secondary Cell Group (SCG). In other words, for a UE configured with dual connectivity (DC), the MCG is a set of one or more serving cells including the PCell and zero or more secondary cells. Conversely, the SCG is a set of one or more serving cells including the PSCell and zero or more secondary cells.

As also described above, the Primary Cell (PCell) may be an MCG cell that operates on the primary frequency, in which the UE either performs the initial connection establishment procedure or initiates the connection reestablishment procedure. In the MR-DC mode, the PCell may belong to the MN. The Primary SCG Cell (PSCell) may be an SCG cell in which the UE performs random access (e.g., when performing the reconfiguration with a sync procedure). In MR-DC, the PSCell may belong to the SN. A Special Cell (SpCell) may be referred to a PCell of the MCG, or a PSCell of the SCG, depending on whether the Medium Access Control (MAC) entity is associated with the MCG or the SCG. Otherwise, the term Special Cell may refer to the PCell. A Special Cell may support a Physical Uplink Control Channel (PUCCH) transmission and contention-based Random Access, and may always be activated. Additionally, for a UE in an RRC_CONNECTED state that is not configured with the CA/DC, may communicate with only one serving cell (SCell) which may be the primary cell. Conversely, for a UE in the RRC_CONNECTED state that is configured with the CA/DC, a set of serving cells including the special cell(s) and all of the secondary cells may communicate with the UE.

As described above, in NR, three different RRC states are supported as different modes of operations for a UE. These three states include an RRC_CONNECTED state, an RRC_IDLE state, and an RRC_INACTIVE state. A UE (or the RRC layer of the UE) may operate in one of these three RRC states. Except for a UL data transmission that is performed during an RA procedure, the UL data transmission may generally be allowed to be performed by the UE only in the RRC_CONNECTED state.

is an RRC state transition diagram illustrating various RRC states and RRC transition procedures that a UE may undergo within a next generation radio access network, according to an exemplary implementation of the present application. The RRC state transition diagrammay include RRC_CONNECTED state, RRC_INACTIVE state, and RRC_IDLE state. In some implementations, the RRC_CONNECTED, RRC_INACTIVE, and RRC_IDLE states may be three RRC states independent of one another. As shown in, a UE may transition among the three RRC states.

For example, a UE may transition to RRC_INACTIVE statefrom RRC_CONNECTED stateor may transition from RRC_INACTIVE stateto any of RRC_CONNECTED stateor RRC_IDLE state. However, as shown in RRC state transition diagram, a UE may not transition directly from RRC_IDLE stateto RRC_INACTIVE statein some implementations. That is, a UE may transition to RRC_INACTIVE statefrom RRC_IDLE statethrough RRC_CONNECTED statein some such implementations. In some aspects of the present implementations, a UE may also transition from RRC_CONNECTED stateto RRC_INACTIVE stateusing an RRC Suspend (or RRC Release with Suspend) procedure. Conversely, the UE may transition from RRC_INACTIVE stateto RRC_CONNECTED stateusing an RRC (Connection) Resume procedure. Additionally, the UE may use an RRC Release procedure to transition from RRC_CONNECTED stateor RRC_INACTIVE stateto RRC_IDLE state, while using an RRC Establish procedure to transition from RRC_IDLE stateto RRC_CONNECTED state.

In some implementations, in an RRC_INACTIVE state, a UE may remain as Connection Management (CM)-CONNECTED (e.g., where the UE has a signaling connection with AMF) and may move within an area configured by the NG-RAN (e.g., RNA) without notifying the NG-RAN. In the RRC_INACTIVE state, the last serving cell (e.g., associated with a gNB) may keep the UE context and the UE-associated NG connection with the serving AMF and UPF.

In some implementations, the RRC_INACTIVE state may support various functions and/or characteristics, such as small data transmission (SDT), PLMN selection, SNPN selection, broadcast of system information, cell re-selection mobility, paging initiated by NG-RAN (RAN paging), RAN-based notification area (RNA) managed by NG-RAN, DRX for RAN paging configured by NG-RAN, 5GC-NG-RAN connection (e.g., both control/user (C/U)-planes) established for the UE, UE AS context stored in NG-RAN and the UE, NG-RAN determining the RNA to which the UE belongs, etc. In some implementations, for NR connected to a 5GC network, a UE's identity (e.g., I-RNTI) may be used to identify the UE context in the RRC_INACTIVE state. The I-RNTI may provide the new NG-RAN node with a reference to the UE context corresponding to the old NG-RAN node.

How the new NG-RAN node is able to resolve the old NG-RAN ID from the I-RNTI is a matter of proper configuration in the old and new NG-RAN nodes. Some typical partitioning of a 40-bit I-RNTI my include, but is not limited to, a UE-specific reference, an NG-RAN node address index, PLMN-specific information, and SNPN-specific information. A UE-specific reference may include a reference to the UE context within a logical NG-RAN node. An NG-RAN node address index may include information that identifies the NG-RAN node that allocates the UE specific part. Network-specific information (e.g., PLMN-specific information or SNPN-specific information) may include information that supports network sharing deployments, and provides an index to the PLMN ID part of the Global NG-RAN node identifier. SNPN may include a small PLMN that is configured by an operator. Each SNPN may be identified by a unique SNPN identity (ID) (e.g., an identifier for an SNPN may be a combination of a PLMN ID and an MD). A configured grant configuration may be associated with an SNPN ID.

In some implementations, the AS Context for a UE in RRC_INACTIVE state may be stored when the connection is suspended (e.g., when the UE is in an RRC_INACTIVE state) and may be restored/retrieved when the connection is resumed (e.g., when the UE transitions from the RRC_INACTIVE state to an RRC_CONNECTED state). The suspension of the RRC connection may be initiated by the network. When the RRC connection is suspended, the UE may store the UE Inactive AS context (and any related configuration received from the network), and may transition to an RRC_INACTIVE state. If the UE is configured with SCG, the UE may release/suspend the SCG configuration upon initiating an RRC Connection Resume procedure. The RRC message to suspend the RRC connection may be integrity-protected and ciphered. Resumption from a suspended RRC connection may be initiated by upper layers when the UE needs to transition from an RRC_INACTIVE state to an RRC_CONNECTED state, or by the RRC layer to perform an RNA update, or by RAN paging, for example, from NG-RAN. When the RRC connection is resumed, the network may configure the UE according to the RRC connection resume procedure and based on the stored UE Inactive AS context (and any related RRC configuration received from the network). The RRC connection resume procedure may reactivate the AS security and reestablish the SRB(s) and DRB(s).

In some implementations, in response to a request to resume an RRC connection, the network may perform any of the following procedures. In some implementations, in response to such a request, the network may resume the suspended RRC connection and send the UE to an RRC_CONNECTED state, or may reject the request and send the UE to an RRC_INACTIVE state (e.g., with a wait timer). In some other implementations, the network may directly re-suspend the RRC connection in response to the request and send the UE to an RRC_INACTIVE state, or may directly release the (RRC) connection and send the UE to an RRC_IDLE mode. In yet other implementations, in response to a request to resume the RRC connection, the network may instruct the UE to initiate a NAS-level recovery (e.g., by sending an RRC setup message to the UE).

In addition, in the RRC_INACTIVE state, the upper layers (or the RRC layer) may configure a UE's specific DRX mechanism. The UE's controlled mobility may be based on the network configuration in the RRC_INACTIVE state, and the UE may store the UE Inactive AS context. Additionally, a RAN-based notification area may be configured by the RRC layer when the UE is in the RRC_INACTIVE state. Furthermore, the UE may perform other functions while in the RRC_INACTIVE state, such as monitoring Short Messages (e.g., that are transmitted with P-RNTI over DCI); monitoring a Paging channel for CN paging (e.g., using 5G-S-TMSI) and RAN paging (e.g., using full I-RNTI); performing neighboring cell measurements and cell (re-)selection; performing RAN-based notification area updates periodically and/or when moving outside the configured RAN-based notification area; and acquiring system information and sending an SI request (e.g., if configured).

Random Access Procedure

In some implementations, two types of random access (RA) procedures may be supported/configured for the UE. For example, 4-step RA type with MSG 1 and 2-step RA type with MSG A. Both types of RA procedure support contention-based random access (CBRA) and contention-free random access (CFRA).

The UE selects the type of random access at initiation of the random access procedure based on the network configuration, for example, as follows:

is a diagramillustrating a random access procedure with 2-step RA type (e.g., for small data transmission), according to an example implementation of the present application. Diagramincludes UEand base station(e.g., a gNB), where UEmay transmit an RRC resume request and/or uplink (UL) data (e.g., small data) to base stationvia a random access procedure with 2-step RA type.

As illustrated in, actionincludes UEtransmitting a random access (RA) preamble and/or an RRC resume request (e.g., MSG A) to base station. MSG A may include a RACH resource and a PUSCH payload. The RA preamble may be transmitted via the RACH resource of MSG A. The RRC resume request may be transmitted via the PUSCH payload of MSG A. Base stationmay configure the RACH resources which may be used to let UEtransmit the RA preamble. In some implementations, the RACH resources may be configured specifically for the small data transmission purpose. UEmay select a RACH resource (for a small data transmission purpose) from the configured RACH resources (e.g., prescribed by combinations of time resources, frequency resources, and sequence resources). Then, UEmay transmit the RA preamble using the selected RACH resource of MSG A, e.g., for the purpose of small data transmission. UEmay transmit the RRC resume request via the PUSCH payload of MSG A. The UL data (e.g., small data) may also be multiplexed with the RRC resume request to be transmitted via the PUSCH payload of MSG A.